Updates in SASfit for fitting analytical expressions and numerical models to small-angle scattering patterns

Area of Science:

• Materials Science
• Condensed Matter Physics
• Biophysics

Background:

• Small-angle scattering (SAS) is a crucial technique for characterizing particle ensembles across diverse scientific fields.
• SASfit is a long-standing, comprehensive software for SAS data analysis, offering specialized tools.
• Continuous development is essential to maintain SASfit's relevance and expand its analytical capabilities.

Purpose of the Study:

• To present recent enhancements and additions to the SASfit program.
• To improve the technical foundation, analytical models, and data processing techniques within SASfit.
• To benefit both existing and new users with advanced functionalities for small-angle scattering analysis.

Main Methods:

• Implementation of new numerical algorithms and a continuous integration practice for software development.
• Upgrades to the plug-in system to facilitate third-party developer contributions.
• Inclusion of new form factors for anisotropic scattering and updates for multiple scattering effects.
• Introduction of the metalog distribution and expectation-maximization regularization techniques.
• Development of new structure factors for ordered nanomaterials and an Ornstein-Zernike solver for particle interactions.

Main Results:

• Enhanced technical basis with improved algorithms and automated software building.
• Expanded scattering models accommodating anisotropy and multiple scattering phenomena.
• Advanced data analysis options including metalog distribution and expectation-maximization.
• New structure factors and a solver for particle interactions, enabling analysis of complex material systems.

Conclusions:

• The presented enhancements significantly broaden the applicability and analytical power of the SASfit program.
• These updates cater to advanced users and facilitate the analysis of complex scattering data from nano- and meso-scaled materials.
• The improvements ensure SASfit remains a state-of-the-art tool for small-angle scattering research.